1. Field of the Invention
This invention relates generally to air freshener devices and cartridges. More particularly, this invention relates to air freshener devices having an evaporation controlled fragrance cartridge which has means for controlling the evaporation of at least two fragrances of different volatilities where the air flow to the cartridge is not obstructed.
2. Description of the Prior Art
Air freshener devices which utilize a fan typically direct air flow at the fragrance container. This construction causes the velocity of the air to decrease as it collides with the fragrance container. Therefore, the air flow is weak and thus, the fragrance output of the air freshener apparatus is deficient.
For example, U.S. Pat. No. 4,432,938, issued Feb. 21, 1984 to Murray O. Meetze, Jr., discloses an apparatus for creating a flow of air past a product capable of being vaporized. This apparatus is specifically designed for use with a device that holds the product for release through a permeable membrane. The apparatus includes components for creating a flow of air past or against the device to distribute the volatile product into the environment.
U.S. Pat. No. 4,301,095, issued Nov. 17, 1981 to Leo L. Mettler et al, discloses an air freshener dispenser. The air freshener dispenser disclosed shows an air flow pattern where air enters the housing in all directions and impinges upon a disk which contains the volatile fragrance. The volatilization takes place as the air impinges upon the bottom surface of the pad. The volatilized liquid escapes in a path that is 360.degree. or a total circle at the point of air entry.
These devices direct air flow at the fragrance container. Therefore, the velocity of the air is decreased as it collides with the fragrance container and fragrance flow is impeded.
The present invention utilizes a device where the air flow is not obstructed. Fragrance vapor is drawn into the air stream by the low pressure created by the action of the fan blade. Therefore, the air-fragrance mixture which exits the device enters the environment at a greater velocity thereby aiding in the dispersion of the mixture.
Some types of air fresheners are designed to disperse a combined fragrance which includes fragrances of high and low volatility. The result of the typical design is that the evaporation of the fragrance of high volatility is much greater the first few days of exposure and thereafter evaporation rapidly falls off. This results in a short lived period when the combined fragrances are disseminated at an optimum level. Therefore, it is desirable to control evaporation of the fragrance.
One example where the evaporation of the fragrance is controlled to allow reproduction of a desired odor is U.S. Pat. No. 3,711,023, issued Jan. 16, 1973 to Dean E. Smith. An air conditioning system is disclosed which releases the evaporated volatile substances into the air to produce an odor. The individual compartments from which the odor is to be formed are stored in individual receptacles and the amount of individual components to be released are controllable. The mixing of various components may be controlled by varying the width of the passage way to vary the proportions of the fragrances being mixed. However, the system is not designed to obtain the even rate of evaporation of fragrances of different volatilities.
U.S. Pat. No. 4,477,414, issued Oct. 16, 1984 to Takayoshi Muramoto et al, discloses an apparatus for evaporating a solution of varying volatility (the solution contains ingredients of high, middle, and a low notes). A certain amount of the volatile liquid is allowed to be evaporated at one time. An evaporative container is used which comprises a container for holding the solution and a water absorbing impregnation element that is fitted to the head of the container and which uses the mechanism of a siphon to supply liquid to be evaporated. The use of a controlled dispenser allows the remaining solution to retain the original mixture of notes. This patent also includes a device wherein the amount of evaporation of the solution absorbed to be released can be controlled by a rotating lid. However, this device does not utilize the volatilities of the fragrances by effectively controlling evaporation through separate cavities.
The present invention addresses the problems associated with the prior art devices and provides an air freshener device that controls evaporation of the fragrances and provides an unobstructed air-fragrance flow out of the apparatus.